C++ Dynamically assign std::map comparator

Question

So I have two classes containing std::map members with effectively identical functionality except that the ordering of one map is std::less and the other std::greater.

Answer 1

No. The comparison function is used to generate the actual data structure -- changing the comparison function would require rebuilding the structure from scratch.

That said, if all you want to do is iterate the structure in reverse order, map is a reversible container, so you can just loop over the structure normally using the reverse iterators.